package com.sky.aspect;

/**
 * @author WangCong
 * 2024/11/10 20:24
 */

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义切面,用于实现公共字段自动填充的处理逻辑
 */
@Aspect
@Component
@Slf4j
public class AutoFillAspect {
    //切入点:对哪些类的哪些方法进行拦截
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut(){}

    //自定义的前置通知:在执行方法之前执行
    //为公共字段赋值
    @Before("autoFillPointCut()")
    public void before(JoinPoint joinPoint){
        log.info("自动填充公共字段");
        //1.获取当前被拦截方法的操作类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        AutoFill annotation = signature.getMethod().getAnnotation(AutoFill.class); // 获取注解对象
        OperationType operationType = annotation.value();//获取数据库操作类型
        //2.获取被拦截方法的参数 -- 实体对象
        Object[] args = joinPoint.getArgs();
        if (args == null || args.length ==0){
            return;
        }
        Object entity = args[0];  // 约定将实体对象放在第一个参数位置
//        准备数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();
        // 3.为公共字段通过反射赋值
        if (operationType == OperationType.INSERT){
            // 新增操作,设置新增时间
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
//                通过反射为对象属性赋值
                setCreateTime.invoke(entity, now);
                setCreateUser.invoke(entity, currentId);
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }


        } else if (operationType == OperationType.UPDATE) {
//             更新操作,设置更新时间
            try {
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
    }

}
